Climate change is a real, perilous phenomenon that the planet would be foolish to ignore. Given that, the vexing question has always been, how do we sensibly protect our environment without manacling our energy-driven economy?

Trouble is, this country has gravitated toward fuel economy standards for vehicles when a simpler, easier to administer option awaits. More on that in a moment.

President Donald Trump is gearing up a rollback of those fuel economy standards. By exactly how much isn’t known yet, but this is a direct hit on former President Barack Obama’s preferred method of cutting tailpipe emissions as one way to curtail global warming.

Obama’s plan forced carmakers to, by 2025, ramp up the average fuel efficiency of new light trucks and cars to more than 50 miles per gallon in lab settings, or roughly 36 mpg in real-world driving. It brought the rest of the country in line with the tough fuel economy standards California enforces.

The Trump administration says the rollback will free carmakers from regulations that have kept them from producing more affordable vehicles. California, said Trump’s Environmental Protection Agency chief, Scott Pruitt, “shouldn’t and can’t dictate to the rest of the country what these levels are going to be.” We often disagree with Pruitt, but here he has a point. If California wants to enforce tougher fuel efficiency standards, by all means, Sacramento, be our guest. But not as a mandate affecting drivers in Illinois and other states.

California won’t surrender easily to Washington. It has the power to enforce stricter air pollution standards, thanks to a special waiver granted under the 1970 Clean Air Act. Twelve other states adhere to California’s stronger standards; taken together, California & Friends represent about a third of the nation’s vehicle market. The state’s attorney general, Xavier Becerra, has said if the Trump administration tries to revoke California’s waiver, his state will fight back. “We’re not looking to pick a fight with the Trump administration,” Becerra says, “but when they threaten our values, we’re ready.”

It remains to be seen how Trump will handle the California conundrum. He could revoke California’s waiver, which likely would yield a protracted court fight. If he takes no action, the waiver will expire in 2025. In the meantime, carmakers would have to choose between producing two distinct lines of cars to meet the different fuel standards — the federal government’s and California’s — or adhering to California’s stricter standards. In a prepared statement Monday, the EPA said the California waiver “is still being re-examined” by the agency.

Because they’re aimed more at manufacturers than at motorists, fuel efficiency standards are an inefficient means to reach a good end: less gasoline consumption.

Trump instead would be smart to embrace a different, smarter idea this page has advocated for some time:

A carbon tax imposed on fuel production would give consumers a choice: Want to save money and the environment? Fine, then consume less fuel than you do today. Prefer your gas-guzzling SUV? OK, but you’ll pay more for every gallon. And if your state wants even more stringent efforts to depress fuel consumption — are you listening, California? — state lawmakers could add a state-based carbon levy to the federal tax.

Think about it this way: Fuel standards complicate life for automakers trying to appease government regulators as well as their own customers. A carbon tax puts the onus on drivers to conserve — or pay.